What's the best neighborhood in Manhattan New York?

I would really like to know this too Im moving to america sometime in the next couple of months/years (who knows) and i need to find the right friendly neighbourhood But so far all i have come across is people saying its dangerous and dont walk around on your own etc.. I wanted to move to upper west side Manhattan it seems like a ideal place to live with being 4 miles from NYC etc, But like i said people are saying its unsafe all over upper east upper west central.. If it is then i would have to rethink my whole move, would want to live somewhere that's this dangerous all the time, Im from england and dont have a clue about these areas and im sure all of these people cant be wrong :(